You known you're allergic when you react to certain substances you've been exposed to before. For instance, you may have eaten shellfish before but the next time you eat foods containing shellfish, you develop rashes.

An allergy occurs when your body overreacts to things that don't normally cause problems for most people. These things are called allergens and your body's overreaction to them are what causes allergy symptoms.

No one really knows why someone develops allergy. Studies have shown that allergy may be hereditary or genetic. Others say that allergy is just something that develops over time and disappears, also over time. But one thing is certain, there are certain specific factors found in the environment that can trigger the body to develop allergy symptoms.

The most common allergen is pollen from trees, grass, and weeds. Allergy symptoms caused by these allergens often occur in the spring (late April and May) and may also occur late in the summer (late May to mid-July). Ragweed allergens may also cause allergy symptoms in the fall (late August to the first frost).

In direct contrast to pollen, which is airborne, molds are contracted by contact through the skin. Mold is common where water tends to collect, such as shower curtains, window moldings and damp basements. It can also be found in rotting logs, hay, mulches, commercial peat moss, compost piles, and leaf litter. Allergy symptoms caused by molds become worse during humid and rainy weather.

Another common type of allergen is animal dander. These are proteins found in the skin, saliva, and urine of furry pets, such as cats and dogs. You can develop allergy symptoms from handling an animal or from coming into contact with house dust, containing dander.

Various more allergens are contained in dust. One of them is dust mites, which are tiny living creatures found in bedding, mattresses, carpeting, and upholstered furniture. These mites live on dead skin cells and other things found in house dust, and coming into contact with them may result in allergy symptoms.

How to Control Allergy Symptoms?

Unless you live in a vacuum, it is extremely difficult to avoid allergens all together. But with a little management and control, you can reduce the occurrence of allergy symptoms caused by these allergens.

Keeping clean is always the first step in controlling allergy symptoms. Before bedtime, it is advisable to shower or bathe to wash off pollen and other allergens in your hair and skin. You can also reduce the amount of mold in your home by frequently cleaning those places where mold often accumulates.

Avoid going outside the home during dry, windy days. Keep windows and doors shut, and use an air conditioner at home and in your car. This is one way to keep yourself from developing allergy symptoms caused by pollen and other airborne allergens.